Abstract
The mechanisms of liquid lubrication in metal forming are studied at a mesoscopic scale, adopting a 2D sequential fluid-solid weak coupling approach earlier developed in the first author's laboratory. This approach involves two computation steps. The first one is a fully coupled fluid-structure Finite Element computation, where cavities in the surface are plastically deformed leading to the pressurization of the entrapped fluid. The second step computes the fluid exchange between cavities through the plateaus, one cavity at a time. This second step consists in solution of the local Couette's equation, at the asperity level, in order to quantify the fluid leakage in the cavity/plateau network using the lubricant pressure computed previously. The numerical simulation is validated by experimental tests in plane strain strip reduction of aluminium sheet provided with model cavities in form of pyramidal indentations. The tests are performed with variable reduction and drawing speed under controlled front and back tension forces. Visual observations through a transparent die of the fluid entrapment and escape from the cavities using a CCD camera show the mechanisms of MicroPlastoHydroDynamic Lubrication (MPHDL) as well as cavity shrinkage due to lubricant compression and escape and strip deformation.
Original language | English |
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Journal | AIP Conference Proceedings |
Volume | 1353 |
Pages (from-to) | 1729-1734 |
ISSN | 0094-243X |
Publication status | Published - 2011 |
Event | 14th International ESAFORM Conference on Material Forming - Queen's University Belfast, Belfast, Ireland Duration: 27 Apr 2011 → 29 Apr 2011 Conference number: 14 |
Conference
Conference | 14th International ESAFORM Conference on Material Forming |
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Number | 14 |
Location | Queen's University Belfast |
Country/Territory | Ireland |
City | Belfast |
Period | 27/04/2011 → 29/04/2011 |